The Integrated Digital Enhanced Network (iDEN) is a network provided by Motorola, and utilized by Sprint Nextel Corporation, for providing service for dispatch calls. As is known, a dispatch call is commonly known as a “walkie-talkie” type of call, such as provided by Sprint Nextel Corporation and identified by the trade names Push-To-Talk (PTT) or Direct Connect. Thus, dispatch communications are half-duplex communications where only one person at a time is able to speak.
The iDEN network is organized into different urban areas, where each urban area covers a wide geographic region. Some subscribers to Sprint Nextel's dispatch service are restricted from placing dispatch calls across different urban areas. Thus, these subscribers are generally known as being Nationwide Direct Connect (NDC) restricted and are only able to place calls within a particular urban area (intra-urban calling). Any attempt to place a dispatch call to another urban area (inter-urban calling) will be rejected by the dispatch call processor, e.g., a dispatch application processor (DAP), that services the caller in the caller's urban.
As is known, to enforce the NDC restrictions, the caller's DAP is able to determine when the caller is attempting to place a call to another urban. The caller's DAP recognizes that the DAP that services the called party resides in a different urban. As a result of the caller's DAP recognizing that the called party's DAP is located in a different urban, the caller's DAP rejects the call request. This NDC call restriction logic is programmed into the DAP.
Whereas this NDC inter-urban call restriction logic is effectively utilized by the iDEN network for dispatch calls between parties that solely utilize the iDEN network, increasingly iDEN network subscribers are attempting to place dispatch calls to other Sprint Nextel subscribers that have migrated to 3G technologies for dispatch calls, to non-Sprint Nextel subscribers that are utilizing 3G technologies for dispatch calls, and to 3rd Party PTT applications like Push-to-X services, where X can be sports, weather, stock quotes, etc. In all of these cases, when a Sprint Nextel subscriber utilizing the iDEN network attempts to place a dispatch call to a called party or application that is not utilizing the iDEN network, the iDEN network must send the call request to an iDEN Gateway (iGW) that provides interoperability between the iDEN network and the non-iDEN network, e.g., a 3G network. Thus, the calling party's DAP must send the call request to the iGW. This presents drawbacks for iDEN calling parties that are NDC restricted.
In the protocol of the iDEN network, the calling party's DAP recognizes the iGW as a different urban. Therefore, if the calling party is NDC restricted, and thus restricted from placing inter-urban calls, the calling party is not able to place dispatch calls to a non-iDEN network through the iGW. This is so because the DAP will reject this call request since the iGW is recognized as a different urban by the DAP when the DAP performs an NDC restrictions check. One approach for attempting to resolve this issue could be to change the NDC restrictions check so that these types of calls are permitted. However, changing the restrictions check could be complex and costly.
Therefore, there is a need to provide a method and apparatus for handling calling restrictions for dispatch calls made from the iDEN network to a non-iDEN network.